feat(datasource):desc字段非必填

backend/src/main/resources/db/migration/V2__dataease_ddl.sql

@@ -40,7 +40,7 @@ DROP TABLE IF EXISTS `datasource`;
 CREATE TABLE `datasource` (
   `id`          varchar(50) NOT NULL DEFAULT '' COMMENT 'ID',
   `name`     varchar(50) NOT NULL COMMENT '名称',
-  `desc`  varchar(50) NOT NULL COMMENT '描述',
+  `desc`  varchar(50) COMMENT '描述',
   `type`  varchar(50) NOT NULL COMMENT '类型',
   `configuration`  longtext NOT NULL COMMENT '详细信息',
   `create_time` bigint(13)  NOT NULL COMMENT 'Create timestamp',